In general, a handle device mounted on an object such as a suitcase for allowing a user to hold can be classified as two types, i.e. rotatable one and irrotatable one. An irrotatable handle device 12 is fixed on a surface 111 of the suitcase body 11 in a certain orientation, as shown in FIG. 1, and cannot be adjusted to any other orientation. Such a handle device 12 lengthens the suitcase by a distance X equal to the length of the handle device 12 so as to occupy more space when accommodated.
Referring to FIG. 2, a rotatable handle device 22 includes a fixed portion 221 and a rotatable portion 222. The fixed portion 221 is consisted of two brick pieces 33 separately mounted on a surface 211 of the suitcase body 21. Each of the brick pieces 33 has a concave hole 331 serving as a mortise for receiving one of the two tenons 332 located at both ends of the rotatable portion 222, as shown in FIG. 3. By this way, the handle device 22 can be pivotally rotated on an axis 2 to any orientation within a range of 180 degrees without obstruction. Because of the free rotation, however, it is difficult for the handle device 22 to be positioned at a desired location.
The handle device generally used on a power supply casing is similar to the latter mentioned above. The disadvantage of uncertain location also appears in the handle device of a conventional power supply. Accordingly, the power supply is subject to collision with external objects owing to the unexpected rotation of the handle device.